The present invention relates to the field of telecommunications; more particularly, the present invention relates to backplanes that enable communication between cards in an enclosure such as a network box.
In telecommunications, cabinets are used at the switching office. Each of these cabinets includes one or more rack mountable enclosures, or network boxes. These enclosures typically contain a number of slots into which cards, or blades, are inserted. The cards are often dedicated to providing a particular communication interface. For example, one card may provide an interface to send and receive SONET data streams, while another card may have an interface to send and receive TDM data streams.
Cards may communicate with each other. However, not all such communication is direct. For example, in order for some cards to communicate with each other, they must go through one or more intermediate cards. This clearly slows down communications. The card-to-card communications occurs over a backplane. Furthermore, the backplanes are often very large, which affects the speed of communications going over the backplane.
Another problem with prior art network boxes is that the slots are usually dedicated to specific types of cards. Therefore, a card of one type cannot be put in every slot. This is usually due to the backplane being configured with ports on certain cards having dedicated, fixed connection to certain card slots.
A network box is described. In one embodiment, the network box comprises multiple card slots. Each of the slots has multiple ports. The network box also includes a full mesh interconnect backplane coupling each of the cards slots to each other using point-to-point serial links. The network box includes at least one card inserted into one of the slots. This card has a controller to maintain information specifying a mapping of connections between each of the ports on each of the card slots in order to configure connections between the card ports of the plurality of card slots.